A disputed territory is land or sea claimed by more than one state, or by a state and a movement seeking its own, where the claim is backed by maps, laws or armies but not settled by a treaty both sides accept. The world has dozens of them, from Western Sahara, about 272,000 square kilometres of desert split by a 2,700 km sand wall, to the Falkland Islands, Crimea, Kashmir, the Spratly Islands and the southern Kurils. They matter because they are where armies face each other, where people carry passports their neighbours do not recognize, and where fishing grounds, oil and shipping lanes are at stake. The clearest way to see them is to travel the world from west to east and stop at each line in turn.
60° West: the Falklands and the Essequibo
Start in the South Atlantic, about 500 km east of Patagonia. The Falkland Islands, around 12,000 square kilometres made up of East Falkland, West Falkland and 776 smaller islands, have been under British administration almost continuously since 1833. Argentina, which calls them the Islas Malvinas, bases its claim on succession to Spanish sovereignty and on the removal of its authorities by a British naval force in January 1833. Argentina invaded in April 1982; British administration was restored two months later at the end of the Falklands War. In a 2013 referendum almost all votes cast favoured remaining a British overseas territory. The 2021 census counted 3,662 people, about 30% of them temporary residents or staff at the RAF Mount Pleasant base. Argentina rejects the islanders’ claim to self-determination, several South American states back Argentina, and most other countries take no side.
Head north along the same meridian to the Guianas. West of the Essequibo River lies a block of rainforest and savanna of about 159,500 square kilometres that Guyana administers across six of its regions and Venezuela claims as its Guayana Esequiba State. The line Guyana uses comes from the 1899 Paris Arbitral Award, which Venezuela has called void since a memorandum published in 1949 alleged a political deal behind it. The UN Secretary-General referred the case to the International Court of Justice, which accepted jurisdiction on 18 December 2020. In December 2023 Venezuela asked its own voters in a referendum whether the region should become a Venezuelan state. The region itself was home to an estimated 125,000 people in 2023, about 15.8% of Guyana’s population.
13° West: Western Sahara and the Berm
Across the Atlantic, on the coast of north-west Africa, lies the largest disputed territory in this tour. Western Sahara was the colony of Spanish Sahara until 1975–76, when Spain tried to hand it to Morocco and Mauritania. War followed: the Polisario Front proclaimed the Sahrawi Arab Democratic Republic, Mauritania dropped its claim in 1979, and Morocco took control of most of the territory, including all the main towns. A UN-sponsored ceasefire came in 1991, but the planned referendum on self-determination, to be run by the UN mission MINURSO, has never been held.
The line on the ground is the Berm, a sand wall about 2,700 km long, lined with land mines, that Morocco built across the territory. Roughly 70% of Western Sahara lies west of it under Moroccan control, and about 30% lies east of it under the Polisario Front, whose government-in-exile is based in Tindouf, Algeria. The UN lists the territory as non-self-governing and recognizes the Polisario Front as representing its people. The Sahrawi republic is a member of the African Union. France and the United States support Morocco, and in 2025 the UN Security Council endorsed negotiating on the basis of Morocco’s autonomy plan. With an estimated 600,000 people, it is one of the most thinly populated territories on Earth.
33° East: Nicosia and the Green Line across Cyprus
Into the eastern Mediterranean, Cyprus has been split since the Turkish military intervention of 1974, which followed a coup backed by the Greek military government. Turkish forces hold the northern third of the island, where the Turkish Republic of Northern Cyprus declared independence; only Turkey recognizes it. Between the two sides runs the UN buffer zone, also called the Green Line, patrolled by the peacekeeping force UNFICYP. It stretches 180 km from Paralimni in the east to Kato Pyrgos in the west, covers 346 square kilometres and varies from under 20 m wide to more than 7 km. It runs straight through the centre of Nicosia, which since the fall of the Berlin Wall has been Europe’s last divided capital. About 10,000 people live and farm inside the zone. In the village of Pyla, Greek and Turkish Cypriots still live side by side.
The Black Sea rim: Crimea, Abkhazia and Karabakh
North across Anatolia and the Black Sea lies Crimea, a peninsula of about 27,000 square kilometres joined to the mainland only by the Isthmus of Perekop, 5 to 7 km wide. The Soviet Union transferred it from Russia to Ukraine in 1954, and it stayed with Ukraine after 1991. In 2014 Russian forces occupied it and Russia annexed it after a referendum that most states do not recognize. A UN General Assembly vote that year, with 100 in favour, 11 against and 58 abstentions, affirmed Crimea as Ukrainian territory. The Crimean Bridge across the Kerch Strait, opened in 2018, is now its direct road link to Russia.
On the Black Sea’s eastern shore, Abkhazia covers 8,665 square kilometres and has about 245,000 people. After the 1992–93 war with Georgia it became de facto independent. Russia, Venezuela, Nicaragua and Syria recognize it; almost every other state regards it as part of Georgia. The crossing point is the Enguri Bridge, an 870 m road bridge from Chuburkhinji on the Abkhaz side to Rukhi on the Georgian side, with Abkhaz, Russian and Georgian checkpoints. It is the only place where vehicles can cross between the two.
Further east in the Lesser Caucasus lies a dispute that has recently ended on the ground. Nagorno-Karabakh, about 4,400 square kilometres inside Azerbaijan, was run by ethnic Armenians as the breakaway Republic of Artsakh from 1994. Azerbaijan regained the surrounding districts and a third of the region itself in the 2020 war, and after an offensive on 19 September 2023 the republic announced it would dissolve. The territory is now under Azerbaijani control, a rare case of a frozen dispute ending on the ground rather than at a negotiating table.
Kashmir, Aksai Chin and Arunachal along the Himalaya
The busiest stretch of this tour runs along the Karakoram and the Himalaya. The former princely state of Jammu and Kashmir has been claimed in full by both India and Pakistan since partition in 1947. India controls about 55% of its land, including Jammu, the Kashmir Valley, most of Ladakh and the Siachen Glacier, and about 70% of its people. Pakistan controls about 30%, in Azad Kashmir and Gilgit-Baltistan. The two are divided by the Line of Control, formalized by the Simla Agreement after the 1971 war, and have fought over the region in 1947, 1965 and 1971, with the Kargil conflict of 1999 on top.
China holds the remaining 15%, above all Aksai Chin, a high desert of about 38,000 square kilometres whose lowest point is around 4,300 m. China administers it as part of Xinjiang and Tibet; India claims it as part of Ladakh. Travel east along the range and the claims swap round. China claims nearly four-fifths of India’s state of Arunachal Pradesh, 83,743 square kilometres in all, as “Southern Tibet”. India holds it up to the McMahon Line, a boundary drawn in 1914 that China does not accept. The two countries fought over both sectors in 1962.
The western Pacific rim: the Spratlys, the Senkakus and the Kurils
Drop south to the South China Sea. The Spratly Islands, a scatter of reefs, banks and cays, are claimed in whole or part by Brunei, China, Malaysia, the Philippines, Taiwan and Vietnam, and all of them except Brunei occupy some features. China’s wider claim follows the nine-dash line, which the Republic of China introduced as early as 1947. In a case brought by the Philippines, an arbitral tribunal under the UN Convention on the Law of the Sea ruled on 12 July 2016 largely in the Philippines’ favour. China did not take part and rejects the ruling. The prize is fishing grounds, oil and gas reserves, and position beside some of the world’s busiest shipping routes.
North-east of Taiwan lie the uninhabited islands that Japan calls the Senkakus, China the Diaoyu and Taiwan the Tiaoyutai. Japan incorporated them in 1895; the United States administered them after 1945 and handed them to Japan in 1972. China and Taiwan argue the islands were Chinese before the First Sino-Japanese War. Japan’s government bought three of them from their private owner in September 2012, setting off large protests in China and Taiwan.
The last stop is between Hokkaido and Kamchatka. The Soviet Union took the whole Kuril chain at the end of the Second World War, and Russia administers the four southernmost islands, Iturup, Kunashir, Shikotan and the Habomai group, as part of Sakhalin Oblast. Japan claims them as its Northern Territories. Under the 1951 San Francisco treaty Japan renounced the Kurils, but it argues that these four were never part of them. The 1956 Soviet–Japanese joint declaration ended the state of war, but the two countries have never signed a peace treaty, and eight decades after 1945 the question remains open.
Several stops deserve a closer look: the Kashmir border dispute, the claims in the South China Sea, the geography of the Crimean Peninsula, and the story of why Cyprus is divided.